The present invention relates to a fluid passage closure system in a compressor for a vehicle air conditioner or a household air conditioner, which hermetically closes the compressor by using a seal cap disposed in the fluid passage of the compressor.
In general, compressors for vehicle air conditioners are assembled as a part of the compressor in a compressor manufacturing plant and the assembled compressors are delivered to a vehicle assembly plant, where the compressors are assembled into vehicle air conditioners. In the compressor manufacturing plant, the compressor is filled with a predetermined amount of lubricating oil before shipment for preventing corrosion and providing sufficient lubrication for the sliding parts of the compressor. Conventionally, a seal cap is located in a fluid passage in the compressor, such as a suction port and a discharge port, to hermetically close the compressor for preventing the leakage of lubricating oil or the ingress of dust or moisture into the compressor during the shipment or storage of the compressors.
Inspection for gas leakage from the compressors is conducted for leakage from the compressors, specifically from the joint through which the compressor is mounted on the vehicle or from any other parts of the compressor. The inspection for gas leakage is conducted by firstly inserting an injection needle through a cylindrical seal cap attached in the fluid passage of the compressor and then injecting gas into the compressor through the injection needle. Then, the compressor is set in a vacuum case and inspected whether or not gas leaks out from the compressor.
Conventionally, there has been two ways of sealing a fluid passage of a compressor by using the cylindrical seal cap, one is sealing by using the cylindrical peripheral surface of the cylinder of the seal cap (hereinafter referred to as “cylinder sealing”) and the other is sealing by using the flat surface of the cylindrical seal cap (hereinafter referred to as “flat sealing”).
Sealing by using cylindrical peripheral surface or cylinder sealing is disclosed, for example, in Japanese Patent application Publication No. 11-82858. The fluid passage closure system disclosed in the Publication No. 11-82858 has a mounting member made of a resin material and a closure member made of an elastic material and fixed to the mounting member. In this fluid passage closure system, the cylindrical closure portion of the closure member is press-fitted in the suction port of the compressor and the mounting member is fixed on the housing of the compressor by a stud bolt that is screwed in the housing, extending through a hole in the mounting member and tightened by a nut. Thus, the cylindrical closure portion of the closure member is press-fitted in the suction port of the compressor, so that the peripheral surface of the cylindrical closure portion of the closure member is closely in contact with the inner wall surface of the suction port thereby to hermetically close the suction port.
A plug for temporarily closing the input-output port by using flat surface or flat sealing is disclosed in the Japanese Unexamined Utility Model Application Publication No. 58-76862. The plug is made of a synthetic resin material having elasticity and a ring-shaped flange closely in contact with the end surface of the input-output port and a cylindrical portion inserted in the input-output port and engaged with the inner surface of the input-output port. The cylindrical portion of the plug has a plurality of slits cut and extending in the axial direction of the plug. The input-output port is closed by the ring-shaped flange, and the slits formed in the cylindrical portion facilitates attachment and detachment of the plug.
Although nothing is mentioned in the Publication No. 11-82858 about the method of inspection for a closure state of the compressor, gas may be injected into the compressor by using an gas injection needle inserted through the closure member made of an elastic material. The hole formed by removing the gas injection needle from the closure member is closed by the elasticity of the closure portion of the closure member used for hermetically closing the fluid passage. Thus, the closure state of the compressor is not impaired by the inspection and, therefore, the inspection for gas leakage from the compressor may be conducted by using the fluid passage closure system as it is.
According to the plug for temporarily closing the fluid passage by flat sealing disclosed in the Publication No. 58-76862, an gas injection needle may be inserted through the ring-shaped top surface of the projection at the center thereof for gas injection into the input-output port for inspection for gas leakage from the compressor. However, the hole formed when the gas injection needle is removed is not closed completely by the elasticity of the plug. Therefore, in an apparatus such as compressor requiring an inspection for the closure state, the plug for temporarily closing the input-output port by flat sealing cannot be used for the inspection for gas leakage. Conventionally, gas is injected into the compressor by using special equipment for gas injection. Then, a plug for temporarily closing a port by flat sealing is set in the fluid passage, and the inspection for gas leakage is conducted. Thus, the operation for the inspection is troublesome and time consuming.
The present invention is directed to providing a fluid passage closure system in a compressor according to which inspection for a closure state of the compressor may be conducted by using a seal cap that closes a fluid passage by flat sealing.